KeyMapItem called in 3DView jumps to execute without invoke

[welford]

Hello,

I have a script which adds a menu to the info panel. That menu contains various exporting scripts that can be selected to bring up a GUI with options for exporting.

I added a shortcut so that I can display that menu in the 3D view (using ctrl+shift+"W") which works as I expect but upon selecting the sub-item that I wish to run the script jumps straight to the Operator's execute() method without calling invoke(). This means that the GUI is never set up ( I am using fileselect_add) and none of the options such as file location are set.

Is there a way to work around this?

Thanks,

James